Miniature Circuit Breaker is a safety accessory with an electro-mechanical mechanism of action. MCB is an automatic switch that opens when excessive current flows through the circuit. It can be reclosed without any manual replacement. A circuit breaker is an automatically-operated electrical switch designed to protect an electrical circuit from damage caused by overload of electricity or short circuit. A circuit breakers function is to detect a fault condition and, by interrupting continuity, to immediately discontinue electrical flow.
MCBs are switches that turn off automatically when there is an overload or a short circuit. After solving the problem in the circuit, the switch can be turned back on, and then the current flows as usual. MCB has several advantages over fuse: MCB is more sensitive to current than fuse. MCB or Miniature Circuit Breaker is a circuit breaker which is used for protection where current ratings are lower. It can be used upto 125A circuits & like MCCBs it also offers protection against overload & short circuit through bimetal & solenoid.
Breakers are installed in an electrical panel (breaker box) and each circuit is attached to a singular breaker. The breaker will monitor the circuit and in the event of a complication such as an overload, the breaker will immediately shut off that circuit. There are about six different types of MCB, which are A, B, C, D, K and Z. Firstly, Type A trips off the circuit when the current exceeds 2-3 times the actual current rating. Since this type is highly sensitive to short circuit, it is better suited for semiconductor devices.
